Method for longitudinally guiding rolling stock, especially a hot-rolled steel strip, and hot-rolling mill for carrying out said method

ABSTRACT

An object of the invention is to reduce structural and strength differences over the width of the rolling stock and to minimize the losses of the rolling stock caused by trimming. The object of the invention is achieved, according to the invention, by guiding the rolling stock ( 5 ) longitudinally and on opposite sides of a laminar cooling region ( 4 ).

The invention relates to a method of longitudinally guiding a rolling stock, in particular, a hot-rolled steel strip and having features of the preamble of claim 1, and to a hot-rolling mile for carrying out the method and having features of the preamble of claim 8.

It is generally known that a rolling stock in a hot-rolling mill, after leaving a finishing rolling train, passes, over a roller table, a laminar cooling region on its way to a reel region.

In the laminar cooling region, the rolling stock is cooled by water to a necessary reeling temperature in order to achieve, as much as possible, uniform structure and strength characteristics over the width of the rolling stock.

Under conditions of the entire manufacturing process of the rolling stock, a non-uniform temperature profile is produced over the width of the rolling stock. This temperature profile can be influenced by cooling the rolling stock with a cooling device, preferably, arranged along the rolling stock and over its width for achieving uniformity. Such a device is disclosed in German Patent 32 30 866 C2 and German Publication DE 199 25 535 A1.

However, the displacement of the rolling stock along the roller table is not always so effected that the rolling stock is uniformly cooled by the above-mentioned device over approximately the width of the rolling stock because the rolling stock has a tendency to lean over for swarming out, that is it leaves sidewise the cooling region predetermined by the cooling device. Thereby, permanently on one side or on alternating sides, the edge regions of the rolling stock have increased deviations of the temperature profile, of the structure, and of the strength in comparison with the entire width. A particular drawback, in this regard, consists in resulting trimming losses; these trimming losses lead to a smaller output.

It is, therefore, an object of the invention to minimize the above-mentioned structural and strength differences and trimming losses of the rolling stock. According to the invention, this object is achieved with features of claim 1 and features of claim 8.

According to the features of claim 1, i.e., according to the method of longitudinally guiding the rolling stock, in particular, a hot-rolled steel strip, the rolling stock after leaving the finishing rolling train, is transported on the roller table in direction of a reel and passes a laminar cooling region located between the finishing rolling train and the reel.

According to the invention, the rolling stock is guided along and on opposite sides of the laminar cooling region, by at least one lateral guide which is formed of extending parallel to each other and spaced from each other, strip guides, and in such a way, that it essentially subjected to cooling medium over its entire surface by a cooing device with shrouding elements arranged above the rolling stock.

This has an advantage that consists in that the rolling stock is prevented from swarming out, i.e., from leaving its transportation direction in the laminar cooling region. Thereby, a uniform temperature profile, with formation of uniform structure, and uniform strength characteristics are achieved over the width of the rolling stock.

A further result of the inventive method consists in that trimming losses are noticeably reduced and, as a result, production output increases.

As it has already been mentioned above, a plurality of lateral guides can guide the rolling stock along the laminar cooling region. The lateral guides are formed, as mentioned, of extending parallel to each other and movable relative to each other strip guides provided on opposite sides of the rolling stock.

The adjustment of the at least one lateral guide to the width of the rolling stock takes place automatically in the embodiment of the invention by measuring the width of the rolling stock after it leaves the finishing rolling train. Thereafter, preferably, a rough adjustment of the at least one lateral guide to the width of the rolling stock is effected and after the head of the rolling stock passed the lateral guide, adjustment to the determined width of the cooling stock takes place.

As it also has been mentioned above, the adjustment of the lateral guide transverse to the transportation path of the rolling stock, according to the invention, takes place dependent on the position of, preferably, arranged above the rolling stock, cooling device with shrouding elements for the liquid cooling medium. In the same way, can, naturally, the mentioned cooling device can be aligned with position of the lateral guide, always having in mind achieving an approximately the same temperature profile over the width of the rolling stock.

According to features of claim 8, the hot-rolling mill has, after the finishing rolling train of the hot-rolling mill, a laminar cooling region arranged after the finishing rolling train and having a roller table for transporting a rolling stock a reel located at the end of the roller table for winding up the rolling stock; and a cooling device located above the rolling stock, a measurement device for determining a width of the rolling stock is arranged between an output side of the finishing rolling train and an input side of the laminar cooling region and which is connected with electronic control of the hot-rolling mill for transmitting signals thereto. Further, e.g., hydraulic control means for controlling the hydraulic piston-cylinder units is connected with the electronic control for receiving signals therefrom. The piston-cylinder units form drive means for adjusting the strip guides to about the width of the rolling stock.

The invention will now be described in detail with reference to the drawings.

The drawings show:

FIG. 1 a schematic view of a laminar cooling region of a hot-rolling mill according to the state-of-the art;

FIG. 2 a schematic view of a laminar cooling region of a hot-rolling mill according to the present invention; and

FIG. 3 a schematic front view of a cooling device with shrouding elements for a liquid cooling medium in combination with a lateral guide of a roller table and which is located above the rolling stock in the laminar cooling region of the hot-rolling mill.

As shown in FIG. 1, a roller table 3 of a laminar cooling region 44, which is formed of a plurality of cooling sections 4.3, of a hot-rolling mill 1 is provided at the output side of finishing rolling train 2. On the roller table 3, a rolling stock 5 in form of a hot-rolled strip is transported in direction shown with arrow 6 toward a reel 7 and is wound up thereon. Before being wound up, the rolling stock 5 is deflected from its preferably horizontal, transportation direction 6 with a deflection mechanism 8.

Between the output side 4.2 of the laminar cooling region 4 and the deflection mechanism 8, there is arranged a per se known, side guide 9 for the rolling stock 5 and which, however, finally serves for winding the rolling stock 5 flatly on the reel.

The laminar cooling region 4 can, as shown here, be formed of a plurality of laminar cooling sections 4.3, wherein each laminar cooling section 4.3 can have a per se known cooling device 10 with shrouding elements 10.1, as shown in FIG. 3.

FIG. 2 shows a laminar cooling region 4, which is per se known from the state-of-the art, with the distinction consisting in that between two, following each other, cooling sections 4.3, there is arranged a lateral guide 11 (see FIG. 3) formed of strip guides 11.1 and 11.2, and between the output side 2.1 of the finishing rolling train 2 and the input side 4.1 of the laminar cooling region 4, there is arranged a measurement device 12 for determining the width of the rolling stock 5.

The measurement device 12, following the logics, is connected with an electronic control, not shown here, of the hot-rolling mill for transmitting thereto signals for processing the acquired measurement results. The electronic control is connected with, e.g., control means, not shown here, for hydraulic piston-cylinder units which form adjustment drives of the lateral guide 11 consisting of first and second strip guides 11.1 and 11.2.

In FIG. 3, the per se known, cooling device 10 is positioned vertically above the rolling stock 5 displaceable on the roller table 3. The cooling device 10 has shrouding elements 10.1 for liquid cooling medium 13.

According to the invention, on both sides of the rolling stock 5, there are positioned, respectively, strip guides 11.1 and 11.2. Both strip guides form the lateral guide 11 that, as shown in FIG. 2, is provided between two, respective, following each other, laminar cooling sections 4.3. Each strip guide is connected with a free end of a respective piston rod 14.1 or 15.1 of, preferably, hydraulic, piston-cylinder unit 14 or 15 r for adjusting the strip guides in accordance with the width of the rolling stock 5.

The means for controlling the piston-cylinder units 14 and 15 would not be discussed here further as it does not constitute the subject matter of the invention.

LIST OF REFERENCE NUMERALS

1 Hot-rolling mill

2 Finishing rolling train

2.1 Output side of the rolling mill train

3. Roller table

4. Laminar cooling region

4.1 Entry side of the laminar cooling region

4.2 Exit side of the laminar cooling region

4.3 Laminar cooling section

5. Rolling stock

6. Transportation direction

7. Reel

8. Deflection mechanism

9. Side guide

10. Cooling device

10.1 Shrouding element

11. Lateral guide

11.1 Strip guide

11.2 Strip guide

12. Measurement device

13. Cooling medium

14. Piston-cylinder unit

14.1 Piston rod

15. Piston-cylinder unit

15.1 Piston rod 

1. A method of longitudinally guiding a rolling stock on a roller table of a hot-rolling mill (1), which after leaving the finishing rolling train (2), is transported on the roller table in direction of a reel (7) and passes a laminar cooling region (4) located between the finishing rolling train and the reel, characterized in that the rolling stock (5) is guided by at least one lateral guide (11) along and on opposite sides of the laminar cooling region (4).
 2. A method according to claim 1, characterized in that the rolling stock (5) is guided by a plurality of lateral guide (11) along and on the opposite sides of the laminar cooling region (4).
 3. A method according to claim 1, characterized in that a width of the rolling stock (5) is automatically determined after the rolling stock passes the finishing rolling train (2).
 4. A method according to claim 2, characterized in that the related lateral guides (11) are adjusted to the determined rolling stock width after the a head of the rolling stock has passed a respective lateral guide.
 5. A method according to claim 4, characterized in that adjustment of the lateral guides (11) to the rolling stock width is effected in a controlled manner.
 6. A method according to claim 1, characterized in that a position of the lateral guides (11) is adjusted dependent on a position of a cooling device (10) with shrouding elements (10.1) for a liquid cooling medium above the rolling stock (5).
 7. A method according to claim 1, characterized in that a position of a cooling device (10) with shrouding elements (10.1) for a liquid cooling medium above the rolling stock (5) is adjusted dependent on a position of the lateral guide (11).
 8. A hot-rolling mill having a finishing rolling train, comprises a laminar cooling region (4) arranged after the finishing rolling train (2) and having a roller table (3) for transporting a rolling stock (5); a reel located at the end of the roller table (3) for winding up the rolling stock; and a cooling device (10) located above the rolling stock (5) and having shrouding elements (10.1) for a liquid cooling medium, characterized in that at least one lateral guide (11) is arranged along the laminar cooling region.
 9. A hot-rolling mill according to claim 8, characterized in that a plurality of lateral guides (11) is arranged along the laminar cooling region (4).
 10. A hot-rolling mill according to claim 8, characterized in that a measurement device (12) for determining a width of the rolling stock (5) is arranged between an output side (2.1) of the finishing rolling train (2) and an input side (4.1) of the laminar cooling region (4).
 11. A hot-rolling mill according to claim 8, characterized in that a position of the at least one lateral guide (11) is adjusted dependent on a position of the cooling device (10) located above the rolling stock (5) and provided with shrouding elements (10.1) for a liquid cooling medium and taking into account uniformity of structure and uniformity of strength characteristics of the rolling stock (5).
 12. A hot-rolling mill according to claim 8, characterized in that a position of the cooling device (10) located above the rolling stock (5) and provided with shrouding elements (10.1) for a liquid cooling medium is adjusted dependent on a position of the at least one lateral guide (11) and taking into account uniformity of structure and uniformity of strength characteristics of the rolling stock (5).
 13. A hot-rolling mill according to claim 8, characterized in that the at least one lateral guide (11) comprises strip guides (11.1, 11.2) arranged on opposite sides of the rolling stock (5) extending parallel to each other, and displaceable relative to each other.
 14. A hot-rolling mill according to claim 13, characterized in that each of the strip guides (11.1, 11.2) is connected with a drive formed as a piston-cylinder unit (13) for effecting parallel displacement of the strip guides. 